1. Field of the Invention
The present invention relates to a digital camera, and in particular to a digital camera that generates an intermediate image having a resolution between an original image and a thumbnail image.
2. Description of the Related Art
A digital camera stores, in a storage medium, an original of an image in which a subject is photographed. In recent years, there have been many digital cameras that include a liquid crystal monitor for verifying images and that display preview images immediately after photographing. Thumbnail images that have a lower resolution than original images are suited for easily displaying images in a short time on such a liquid crystal monitor. For this reason, it has been common to store, in the storage medium, compressed data of the thumbnail and the original of the photographed image as a single file.
However, when the pixel number of a photographing sensor such as a CCD or a CMOS is large, the resolution of the thumbnail image has been insufficient for verifying the photographed focus. An intermediate image having a resolution between the original image and the thumbnail image is effective for achieving this object.
However, the problem arises that the photographing interval becomes long when an intermediate image that has a higher resolution than a thumbnail image is generated and stored in the storage medium per photographing. This is because, in order to generate and display the intermediate image after photographing, the next photographing cannot be carried out during this processing, and it takes a long time until preparation for photographing the next image is finished.